North Central ND (6/16/11)

Information from North Central ND, including updates on Canola and Rust in Small Grains.

Canola:

Flea beetle activity has increased
since last week. We are catching both
crucifer and striped flea beetles in our traps.
Damage in area fields has ranged from 10-40% defoliation. Much of the canola in the area was planted
later than normal with some seeding occurring into the first week of June. The majority of the canola is in the two to
four leaf stage. Canola is susceptible
to flea beetle damage until the six leaf stage.
The insecticide residue from seed treatments is effective for about
21-26 days (Jan Knodel, Extension Entomologist). Producers who planted canola prior to May 27
should be checking their fields for flea beetle activity. If the 25% defoliation threshold has been
reached a foliar insecticide application is recommended.

Small Grains- First
Case of Rust in Wheat for 2011:

We observed the first
case of rust for the 2011 season in a commercial winter wheat field south of
Minot. Symptoms of stripe rust and leaf
rust were observed on winter wheat plants in the boot stage. Fungicides that are used to control tan spot
and Fusarium head blight (scab) are also effective against the rust
diseases. Tan spot has been found in
every wheat field surveyed. On average,
61% of plants in fields are infected with an average severity of 8%. Bacterial blight has been found in about 70%
of fields with 50% of plants in infected fields showing symptoms of this
disease. In barley, spot blotch and net
blotch are common throughout the area.
Small grain aphids are present in low numbers in some fields and thrips
larvae have also been found in a number of fields. We continue to remain vigilant for barley
yellow dwarf virus. If this virus is
found in wheat or barley fields, aphids should be controlled much sooner than
the current threshold (85% of stems with at least one aphid).